Bruce E. Johansen: The world-wide slime smackdown

Published 7:51 pm, Friday, August 23, 2013

Human beings, narcissistic creatures that we are, pay too little attention to what goes on out of sight -- for example, in the two-thirds of the Earth that is covered with salt water.

Now comes disquieting news from the shore. Jellyfish love warm water, especially polluted water. Human beings are serving them a dream habitat, and smacks of slime are multiplying rapidly.

Our grandchildren may grow old in a time when jellyfish are the oceans' dominant species. Jellyfish have been called "the cockroaches of the open waters."

On the shores of the Sea of Cortez, in northwestern Mexico, most fish are gone, but "cannonball jellies" have arrived. Former fishermen are loading their boats with the jellies, salting them and shipping their new harvest off to China, where, wrote Erik Vance in Harper's, "They are a bland sort of staple."

By the summer of 2004, reports indicated that jellyfish populations were on the rise in Puget Sound, the Bering Strait and the harbors of Tokyo and Boston. "Smacks" or swarms of jellyfish shut down fisheries in Narragansett Bay, parts of the Gulf of Alaska and sections of the Black Sea.

Near Barcelona, Spain, fishermen found their nets slimed with jellyfish as more than 300 beachgoers per day were treated for stings during the summer of 2008.

All over the world, jellyfish have been proliferating as their predators have been over-fished, pollution has depleted oxygen levels and water temperatures have gradually risen.

During 2008, beaches were closed because of jellyfish swarms on the Cote d'Azur in France, the Great Barrier Reef, of Australia, and at Waikiki and Virginia Beach in the United States. In Australia, where the deadly Irukandji jellyfish is expanding its range in warming waters, the number of jellyfish stings rose to 30,000 treated cases in 2007, double 2005's total.

A jellyfish smack sixteen kilometers square at a depth of 35 feet late in 2007 invaded the Northern Salmon Co., Northern Ireland's only salmon farm, killing more than 100,000 fish, at a cost of more than $2 million.

The Torness nuclear power station in Scotland shut down its two reactors June 28, 2011. after a huge smack of jellyfish clogged the water intakes for its cooling towers. The French company EDF Energy operates the power station.

Those stresses include increased water temperature, a rise in nutrients (from fertilizers and sewage), and depleted stocks of other fish, often caused by over-fishing, which removes the jellyfish's competitors. All of these changes are usually human-caused, according to Graham.

In 2002, a report appeared in the Boston Globe describing a massive infestation of jellyfish in Narragansett Bay and Long Island Sound.

"Eventually it seemed that our deck was coated with Vaseline," said Captain Eric Pfirrmann, who works for Save The Bay, a group whose members engage in environmental issues related to Rhode Island's Narragansett Bay.

The combjelly's reproductive cycle adjusts to the warmth of the water in which it lives. Populations usually explode during the warmth of late summer and early autumn.

Narraganset Bay has warmed an average of 3.4 degrees F during the past 20 years, while between the late 1970s to 2001, the average temperature of Long Island Sound during for the first three months of each year has increased about 8 percent, from 37.4 degrees F to 40.2 degrees F.

In 2013, a United Nations report found that overfishing in the Mediterranean and Black seas was removing top predators, as jellyfish populations jumped. The report, "Review of Jellyfish Blooms in the Mediterranean and Black Sea," published by the U.N. Food and Agriculture Organization's General Fisheries Commission, said, "It is clear that a new type of human approach to marine ecosystems in general is needed to prevent and face a phenomenon such as the jellyfish blooms."

The FAO report the jellyfish prey on fish eggs and larvae as they compete for the same food sources as fish populations that already are declining because of overfishing.

In coming years, jellyfish could replace fish in the world's oceans, according the report, which raises the possibility of "a global regime shift from a fish to a jellyfish ocean." Welcome to the future.